This is not a reference to the recent three decades of rapidly increasing global temperatures, rather it is a reference to an aniversary of the first appearance of the term “global warming” in the peer reviewed literature. The paper was by Wally Broeker and titled “Are we on the brink of a pronounced global warming?”

Real Climate has an interesting post on the details of this paper. The short version is that despite numerous considerations in the paper that have played out differently than hypothesized, the overall prediction of temperature by the end of the 20th century was remarkably accurate.
In this paper, Broecker correctly predicted “that the present cooling trend will, within a decade or so, give way to a pronounced warming induced by carbon dioxide”, and that “by early in the next century [carbon dioxide] will have driven the mean planetary temperature beyond the limits experienced during the last 1000 years”. He predicted an overall 20th Century global warming of 0.8ºC due to CO2 and worried about the consequences for agriculture and sea level.
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To those who even today claim that global warming is not predictable, the anniversary of Broecker’s paper is a reminder that global warming was actually predicted before it became evident in the global temperature records over a decade later (when Jim Hansen in 1988 famously stated that “global warming is here”).
Not that the history started there. Check out Spencer Weart’s History of Global Warming which begins over 150 years ago when even the most hard-core conspiracy theorist will struggle to connect it to a UN quest for world domination.
So this is something to keep in mind when climate inactivists insist we need to wait and see how these “global warming predictions” will play out. We have waited. Reality since those early predictions, plus impressive successes of admitedly limited global climate models are more than enough to realize we must act now and act aggressively to avert what looks more and more likely to be a terrible toll on humanity and all life on this planet.